1. Field of the Invention
The present invention relates to toy rocket launcher sets having a toy rocket and rocket launching device. In particular aspects, the invention relates to such rocket launcher sets wherein a compressed fluid, such as air, is used to propel the rocket.
2. Description of the Related Art
Toy rocket sets have been used and enjoyed by children for a long time. A number of rocket launcher sets are known that utilize compressed fluid, usually air, to propel the toy rocket skyward. Typical problem areas for these rocket launcher sets include the launching mechanism and the means by which a parachute for the rocket is deployed.
Many conventional compressed fluid rocket launcher sets are unable to launch a rocket to a very high altitude because of inherent limitations in the launching mechanism. Some compressed fluid launchers rely upon an interference fit-type seal that is formed between the rear opening of the rocket and the mouth of the fluid supply. Fluid pressure is built up within the body of the rocket until the grip provided by the interference seal is overcome. One such system is described in U.S. Pat. No. 5 ,188,557 issued to Brown. With these systems, the amount of fluid pressure that can be built up is limited by the grip of the interference seal. Further, as the rocket set ages, the interference seal typically degrades due to wear and tear and may not easily be replaceable. Degradation of the seal causes loss of performance for the rocket.
U.S. Pat. No. 2,733,699 issued to Krinsky describes a compressed air launching mechanism wherein a knob is depressed to cause previously pressurized air to enter the launching chamber of the launcher and, thus, launch the rocket. While such a system is effective in permitting sufficient air pressure to be built up for a successful launch, it adds a level of complexity to the toy that is undesirable.
It is a preferred feature for a toy rocket set to have a parachute that deploys from the rocket during its flight to slow the decent of the rocket toward the earth. The parachute is both a visual treat and, as a practical matter, helps prevent structural damage to the rocket from a hard landing. Additionally, a deployed parachute is a valuable aid in locating the landed rocket. However, the process of successfully deploying a parachute is problematic. It is desirable to have the chute deploy at about the time the rocket has stopped rising and begins its decent. An earlier-deploying chute will slow the rocket""s ascent, while a later-deploying chute may not sufficiently slow the rocket""s fall, thereby allowing damage to occur.
Some systems are known that have attempted to address the problem of deploying the chute in flight. U.S. Pat. No. 5,407,375, issued to Johnson, describes a velocity dependent chute release in which the parachute is initially stored within compartment in the rocket. When the rocket is launched and reaches its apogee, a velocity dependent chute release mechanism causes a hatch on the nose of the rocket to open. With the hatch opened, the parachute within may deploy and open. In practice, however, the release mechanism may not be effective to cause opening at the desired time. In addition, the release mechanism is relatively complex being made up of numerous small parts.
U.S. Pat. No. 1,079,200, issued to Wilde, describes an elongated, tubular toy rocket having a parachute affixed to a first weight retained within a rear portion of the rocket body. The weight is initially secured against axial movement within the rocket body by a rod. After the rocket is launched, reaches its apogee and noses over to descend, a second weight slides forward inside of the rocket and triggers a latch. Triggering of the latch allows the rod and first weight to move rearwardly inside the body of the rocket and, thereby, permitting the parachute to fully deploy and open. Wilde""s arrangement is prone to failure when actually used. The latch does not always release the rod, as intended.
An improved rocket launcher set, which addresses the problems of the prior art, would be desirable.
The present invention features a toy rocket set that includes a rocket and a launcher for the rocket that utilizes compressed air to launch the rocket. The launching mechanism for the rocket set features a launching tube into which the rocket is inserted. The upper end of the launch tube has an end cap secured thereupon by a threaded connection. An annular elastomeric element, i.e., a common O-ring, is retained between the end cap and the launch tube body. As the end cap is tightened onto the launch tube body, the elastomeric element is compressed resulting in a frictional engagement with a radially enlarged nose cone on the rocket. Fluid pressure is then increased within a chamber within the launch tube tending to force the rocket upwardly out of the upper end of the launch tube. Once the fluid pressure increases to the point where the upward force upon the rocket overcomes the frictional forces between the elastomeric element and the nose cone, the rocket is launched from the launch tube. It is possible to adjust the tightness of the end cap, thereby increasing the frictional forces retaining the rocket within the launch tube and requiring a greater fluid pressure build up in order to launch the rocket. Thus, by selectively tightening the end cap, a greater maximum height for the rocket can be achieved.
The toy rocket has a novel and advantageous parachute deployment mechanism. The edges of a parachute are secured to the rear end of the rocket body by several links. The centerpoint of the parachute is secured by a tether to a removable link in the rocket body. The removable link is retained within the rocket body by a slidable rod. The nose cone of the rocket is weighted so that, when the rocket begins its descent, it will invert to a nose down position. During flight, when the rocket inverts, the rod slides within the rocket body to release the link and permit the parachute to deploy to an open position. In practice, this deployment mechanism has proven effective and reliable.